Looking for McLaughlin Connelly Family - Dublin City 1830's

We thought we found our GGG Grandparents John & Mary Ann McLoughlin in Ballymoney, Northern Ireland (married 1828, died 1870 and 1864 respectively) and my DNA showed up in 23andme as strongest area - Dublin City origination. We searched for them in Dublin, and found James Connelly 1830 and 1835 (what could be my GG grandfather). He had a brother George that we can not find...thinking maybe George was born 1830 and James 1835? The years are only a couple off from what we thought.

William McLaughlin is listed as witness on the marriage certificate of John and Mary Ann in 1828 Ballymoney, and as god father to James 1830 in Dublin City. Does anyone have connection to any of these names? We don't know if it's a coincidence that they show up in 2 places, or how we can find other family. My GG Grandfather James Connelly married Elizabeth Flynn in CT and had sons in New Haven CT starting in the 1860's named John, George, Peter, James, Hugh, Miles. Looking for any connections in Ballymoney or Dublin with Mary McLoughlin or John Connelly. Thank you!!